ht it. The perfume
must have carried far from the room where the female was, out into the
woods where it was perceived, and followed up to its source by the
male moths.

Such perfumes are very generally produced by little pockets or glands
in the skin, the secretion having, in the case of insects, birds and
mammals, an oily nature. In mammals they are largely produced by both
males and females, and serve to attract the sexes to one another.
Hairs are situated close to the minute odoriferous glands and serve an
important part in accumulating and diffusing the characteristic
perfume. Musk and civet are of this nature, and it is a significant
fact that these substances are used as perfumes by human beings. It
would seem as though mankind had lost either the power of
satisfactorily perceiving the perfumes naturally produced by the human
skin, or that the production of such perfumes had for some reason
diminished. Either condition would account for the use by mankind of
the perfumes of other animals and of flowers. There are a variety of
odorous substances produced by different parts of the human body, of
which some are agreeable and others disagreeable. One of the most
curious facts in regard to odorous bodies is the close resemblance
between agreeable and repulsive odours, and the readiness with which
the judgment of human beings may pronounce the same odour agreeable at
one period or place, and disagreeable at another. There also seems to
be a "dulling" of the power to perceive an odour which is a
consequence of constant exposure to that odour. Thus the Chinese say
that Europeans all smell unpleasantly, the odour resembling that of
sheep, although we do not observe it; whilst Europeans notice and
dislike the smell of the negro, a smell of the existence of which he
is unaware. The blood of animals, including that of man, has, when
freshly shed, a smell peculiar to the species, which has not, however,
any resemblance to that of the skin or of the waxy glands of the same
animal.

It seems that in regard to the exercise of the sense of smell by man,
we must distinguish not only greater from less acuteness and variety
of perception, but in the case of this sense-organ, as in regard to
the others, we must distinguish "unconscious" from "conscious"
sensation. All our movements are guided and determined by sensations
to touch and sight, and to some extent, of hearing, of which we are
unconscious. A vast amount of our sense-exp